The hunt for a former Los Angeles police officer suspected in three killings entered a fourth day in snow-covered mountains Sunday, a day after the LAPD chief ordered a review of the disciplinary case that led to the fugitive's dismissal and new details emerge of the evidence he left behind.

Officials will re-examine the allegations by Christopher Dorner, 33, that his law enforcement career was undone by racist colleagues, Police Chief Charlie Beck announced Saturday. While he promised to hear out Dorner if he surrenders, Beck stressed that he was ordering a review of his 2007 case because he takes the allegation of racism in his department seriously.

"I do this not to appease a murderer. I do it to reassure the public that their police department is transparent and fair in all the things we do," the chief said in a statement.

Authorities suspect Dorner in a series of attacks in Southern California over the past week that left three people dead. Authorities say he has vowed revenge against several former LAPD colleagues whom he blames for ending his career. The killings and threats that Dorner allegedly made in an online rant have led police to provide protection to 50 families, Beck said.

A captain who was named a target in the manifesto posted on Facebook told the Orange County Register he has not stepped outside his house since he learned of the threat.

"From what I've seen of (Dorner's) actions, he feels he can make allegations for injustice and justify killing people and that's not reasonable," said Capt. Phil Tingirides, who chaired a board that stripped Dorner of his badge. "The end never justifies the means."